Electric railway-signal



3 Sheets-Sheet 2.

' AA 53%;; SIP-Ins (No Model.)

s. TOMPKIN S. BLEGTRIG RAILWAY SIGNAL.

Patented Mar. 31, 1891.

WITNESSES TN: mums Perms cm, mom-mum, wnsumn'mn, n e.

. (No Model.) 3 She'efs-Sheet 3.

S. TO'MPKINS. ELECTRIC RAILWAY SIGNAL.

Patented Mar. 31, 1891.

WITNESSES $8 P511518 :0 mam-Yum, wAemuamu, vrc.

UNITED STATES PATENT OFFICE.

STONElVALL TOMPKINS, OF- KNOXVILLE, TENNESSEE, ASSIGNOR OF ONE IIALF TO CHARLES E'VAWTER, OF CROZET, VIRGINIA.

ELECTRIC RAILWAY-SIGNAL.

SPECIFICATION forming part of Letters Patent No. 449,639, dated March 31, 1891.

Application filed December 9, 1889. Serial No. 333,089. (No model.)

To all whom it may concern.-

Be it known that I, STONEWA L TOMPKINS, a citizen of the United States, and a resident of Knoxville .in the county of Knox and State of Tennessee, have invented certain new and useful Improvements in Electric Railway Signals,of which the followingis a specification.

My invention relates to apparatus employed to transmit signals to and from moving trains generally, and particularly to that class of such apparatus which give notice, by automatic operation of electric bells or other devices, to engineers upon their engines, of the proximity of other engines upon the same track.

It is the object of my invention to provide an apparatus of the above character which shall be economical in construction and at the same time attain certain desirable improvements in operation of which apparatus of this class as heretofore constructed and arranged hasv not been capable.

In the accompanying drawings isillustrated and herein described certain apparatus embodying a preferred form of my invention, and likewise certain modified forms thereof, the particular subject matter claimed as novel being hereinafter definitely specified.

In the drawings Figure 1 is a top plan view of a railroad track provided with sectional conductors arranged in accordance with my invention, showing also the application ofan especial continuous conductor which is in this instance employed as a conductorin the stead of one of the rails of the track, showing also engines in place upon said track. Fig.

2 is a detail perspective view of the brushes and their connections as employed in connection with the apparatus of Fig. 1. Fig. 8 is a top plan view of a modified form or arrangement of the conductors, showing engines provided with brushes in a correspondingly modified arrangement. Fig. 4 is a top plan view of another modified arrangement of conductors.

Referring first to Figs. land 2 of the drawings which represent the preferred embodiment of my invention, A represents a railroad track of the ordinary character of which one termination is designated Y and the other Z, the rails of said track being designated a a B B B are engines traveling upon said track, the direction of their travel being indicated by the arrows. The engines are equipped with batteries and bells, and I find it preferable to provide two batteries and two bells in connection with each, to place one battery and bell together in one or forward circuit, and the other battery and bell in the other or rear circuit. The batteries and bells may be of any preferred variety, although I prefer to employ bells of the character which make a single stroke each time the current is set up in the circuit in which they are placed, and said devices may be situated Wherever convenient upon the engine. In all of the engines the forward battery and bell are lettered b and the rear battery and bell b Contact devices or brushes in connection with the respective batteries are mounted in each engine. Any preferred form of coutrivance adapted to the purpose may be employed, but I find the following to be an advantageous arrangement. 0 C, Fig. 2, are a pair of axles supported in any preferred manner in the engine frame-work. Upon the respective ends of the axle O are mounted a pair of brushes 0, and upon the respective ends of the axle O are similarly mounted a pair of brushes c. The brushes are conveniently of the form shown, and at their upper ends each embodies a hub or bearing by means of which they are mounted upon their axles and left free for slight axial rocking movement thereupon. The brushes are also capable of movement in the direction of the length of the axles, and

-are retained upon the axles by the nuts c with which the extremities of said axles are equipped. The lower extremities of the brushes are adapted to make contact with the conductors. In the employment of the sectional conductors hereinafter described, small interspaces will exist between the adjacent ends of meeting sections. To preclude the possibility of one of the brushes lying, when the engine stops, between said meeting ends and out of actual contact with the conductors, 1 form each brush with an extension in the nature of a pivoted arm, which, being a part of the brush itself and in circuit with it in effect makes the contact portion of each brush of such length that it cannot all lie between two meeting sections. In Fig. 2 I show the two brushes nearest the eye as so formed.

In practice they are all, if found desirable, to be so formed, but for clearness of illustration I do not so herein illustrate them. Referring to said Fig. 2, c are the pivoted arms, each secured by a pivot, 0 to its appropriate brush, so that each rests by its own weight down upon the conductor with which the brush to which it is connected is in contact. (Z is a yoke connecting the brushes 0 c, and d is a yoke connecting the brushes 0 c, to which yokes, about midway of their respective lengths, are pivotally attached the respective extremities of a cross bar d, to which is rigidly connected a vertical rotatable bar D equipped conveniently at its upper end with a hand wheel D Rotation of the hand wheel will occasion, as will be apparent, the longitudinal movement in opposite directions of the two yokes, and consequently of the brushes, whereby the latter may be accurately adjusted, in whatever direction the engine may face, to make contact with the appropriate conductors, whereof hereinafter. All of the brushes are properly insulated from the surrounding framework and the two designated 0 c are in circuit with the battery and bell I), while the two designated c are in circuit with the batteryb". A continuous conductor, which I design ate E, extends along the track at a given distance from and in parallelism with the rail a This conductor, the general formation and material of which are not important, is co-extensive with the railroad track in connection with which it is employed, and is conveniently made of a wire or strip of conducting material c supported conveniently at about the level of the tops of the rails in any preferred manner. In the drawings I show said wire or strip c as supported upon a conductor bracket, being a continuous boardlike supporter, c set on edge and affording firm resistance to the weight-and pressure of the brushes. Instead of supplying a special continuous conductor, however, one of the rails of the railroad track may be employed for the same purpose for which said. continuous conductor is used. Two series ofconductor sections extend along the track, separated a convenient distance from each other, and in parallelism with, and a given distance from, the rail a. These conductor sections are, mechanically considered, conveniently constructed in the manner described with reference to the continuous conductorE. The sections of one series (in Fig. 1 that farthest from the track) are of a uniform length, and the sections of the other series, are, for a reason hereinafter explained, while of the same average length as the sec tions of the first mentioned series, alternately longer and shorter than said sections. Each section is insulated from the two sections in the same series adjacent to its respective ends, but is mechanically extended toward said adjacent sections in such manner that the smallest possible interspaees remain. The conduct-or sections and continuous conductor are normally out of circuit. A group of sections consisting of a selected number of alternate membcrsof one series and distributively extending abreast of a given length of the track, are electrically united, by connections out of range of the brushes, and a group of sections consisting preferably of a like number of at ternate members of the other series and extending abreast of a given length of the track longitudinally adjacent to the length first mentioned, are similarly electrically united, and the adjoining end members of'said two groups are electrically united by a wire extending across from one series to the other. A similar arrangement of connections is resorted to with reference to the alternate sections omitted from the groups mentioned, they being in turn, in conjunction with sections in portions of the series not covered by the groups first mentioned, formed into groups in the two sections, and similarly cross coupled. Thus, referring to Fig. 1, the sections g? g g g g g g f are electrically connected by uniting wires to form a group in the inner series of sections, and the seetionsf f fff f ff f are electrically connected by uniting wires to form a group in the outer series of sections, and the section g is connected with the section f by the cross wire h. Thus, again, the sections 9 g g" g g" g" g g" (certain of which were the alternately omitted sections of the group composed of the sections are electricallyconnected by uniting wires to form a group in the inner series of sections, and the sections f f f f" f' f f ff (certain of which were the alternately omitted sections of the group composed of the sections f are electrically connected by the uniting wires to form a group in the outer series of sections, and the section 9 is connected with the section f by the cross wire 7t. Thus, again, the sections f g g g g g j" gf (certain of which were the alternately omitted sections of the group composed of the sections 9) are electrically connected by uniting wires to form a group in the inner series of sections,and the sections f f f f f (certain of which were the alternately omitted sections of the group composed of the sections f are electrically connected by uniting wires to form a group in the outer series of sections, and the section 0" is connected with the section f by a cross wire 7L.

It will from the foregoing be understood that in the arrangement shown in Fig. 1, the sections contained in each series are all included in one or the other groups; that each group in one series has its corresponding group, abreast however of a different portion of the track, in the other series, and that the members of each pair of groups are joined at their meeting ends; that while the members of different groups in a series are interdisposed they are, electrically considered, distinct; and that, upon the formation of a group in eitherseries, halfof the alternately omitted sections are included in one, and half in the other, of the two adjoining groups in the same serles.

'group of sections in the inner series,is-

The forward circuit of each engine is so arranged that its positive and negative poles are represented by its right and left hand brushes respectively. The arrangement of the rear circuit is the reverse of the forward, and its positive and negative poles are represented by its left and right hand brushes respectively. WVhen an engineis placed upon the track to travel toward Z its front right hand brush 0 is arranged to make contact with the inner series of conductors, and its rear right hand brush is arranged to make contact with the outer series of conductors. The two brushes 0 c on the left side of the engine are both arranged to make contact with the continuous conductor E, when a continuous conductor E is employed instead of the rail of the track, as seen in the engines of Fig. 1.

The operation of the system shown in Fig. 1 will be understood from the following description: Assume the engine B stationary upon the track, and the engine B traveling toward it from the rear. The said engine B is through its right hand brush a in contact with the outer series of sections, and through its left hand brush 0 in contact with the continuous conductor E. It will be apparent that so soon as the circuit set up through the rear bell and battery b of the engine B, the brushes connected with said bell and battery, the conductor E, and the group of sections in the outer series, cross wire, and connected closed, the striking bell b of said engine B will be rung. The engine B is, through its right hand brush 0, in contact with the inner series of sections, and through its left hand brush 0 in contact with the continuous conductor E, and therefore the circuit will, every time the right hand brush 0 of the moving engine B arrives at and makes contact with a section of that group of sections of the inner series, which corresponds to and is connected with the group with a member of which the right hand brush 0 of the engine B is in contact, the front striking bell b of the engine B, will ring to indicate the pres ence of an engine in front, and the rear striking bell 19* of the engine B will ring to inclicate the presence of an engine in the rear. Thus, in said Fig. 1, said right hand brush 0' of the engine B is in contact with a section f and its right hand brush 0 in contact with.

the section 9 The right hand brush 0 of the engine B is in contact with a section 9 and belongs to the group corresponding to the group to which said section f belongs, and therefore the forward striking bell of the engine B, and the rear striking bell of the engine B, have, as stated, rung. \Vhcn, in the travel of the engine B, its right hand brush 0 passes over the section g both striking bells will be silent but both striking bells will again ring when the right hand brush 0 of the engineB makes contact with the succeeding section g From the frequency with which said striking bells ring, therefore, the engineers may readily calculate the speed at which engines which close their circuits are running. \Vhen the right hand brush 0 of the engine B and the right hand brush 0 of the engine B are at the same moment in contact with different members of the same group, no ringing of either of said bells is occasioned thereby, as both said brushes constitute the positive poles of their respective batteries and their currents are hence in'opposition.

The engine B is, in Fig. 1, represented as upon the track in front of the engine B, and traveling toward the latter. The arrangement of the brushes of engines when running toward the Y end of thetrack, is the reverse of the arrangement resorted to when running toward its Z end, as will be seen by comparing the engine B with the engines'B and B. Thus the forward battery and hell 1) of the engine B have their brush cwhich is nearest the sectional conductors, in position to make contact with the outer series of sectional conductors, and their brush 0 on the same side in position to make contact with the inner series of sectional conductors. hen said engine B is upon the tracks in the region which itis represented in the drawing'as occupying, and the temporarily stationary engine B is upon the track with its left hand brush 0 upon the conductor E, and its right hand brush'c upon the conductor 9 the striking bells b of both engines will ring every time the left hand brush 0 of the engine B makes contact with a section f Said engine B is represented as about to arrive at the first section f and until it does so arrive both said bells b will remain silent. Vere the engines B and B both actively traveling toward each other, said engine B instead of remaining in contact with the sec- .tion g would pass onto the next section g then to the next section then to the next section g and the engine B in its travel passing and making contact with the same number of sections, it might be possible, if the sections of the two series were of uniform length, for the brushes of the two engines approaching each other and both traveling at the same rate of speed to both cross the interspaces in corresponding groups of sectional conductors at the same moments. If this were the case a less number of strokes of the bells would be occasioned than if, as is desirable, the engines made contact with sections in circuit with each other at different moments, each contact being accompanied by a stroke of the bell. It is in order to avoid the coincidence mentioned that the sections of with a rail of the track, which thereupon bcpassing loosely by the side of the sectionsv with which they are not connected, but it is apparent that they may be supported by being secured to the omitted sections in any position out of range of the brushes. The cross wires h also may be applied in any convenient manner and may if desired be simply hung between the sections which they unite, in which application they are to be sufliciently long to droop out of range of the brushes.

In Fig. 3 is shown a modified arrangement of sectional conductors in. connection with which the system could be carried on. In this arrangement three series of sectional conductors are employed and one continuous conductor, being one of the rails of the track, or a special continuous conductor E. The sections of two of the series, namely, the inner and Ollt01,t16 of the same length, and

said sections are staggered or arranged so as to break joints. I designate the sections of the series nearest the track M M M and the sections of the series farthest from the track N N N The sections of the third series, which is the center one, are only half as long as the sections of the other two series, and I designate the said sections O O 0 0 The end of the section 0 is connected by a cross wire h with the conductor N, the end of the conductor 0 is similarly connected with the conductor M, the end 01' the conductor 0 is similarly connected with the conductor N and so on. The conductor sections may be made in the manner hereinbefore described. P I are two engines, each of which is provided with two batteries and bells as in the case of the two engines hereinbefore described, and each of which is provided with brushes. The engine I traveling toward the Y end of the track has mounted in connection with its forward bell and battery I) on the side of the engine next to the sectional conductors, two brushes in circuit with each other, one of which is in contact with a section of theinner series of sectional conductors and the other of which is in contact with the outer series of sectional conductors,and has also a brush in contact with the continuous conductor, while its battery and bell b have a single brush on the side of the engine nearest the sectional conductors which is in contact with the intermediate series of sections,-and has also a brush in contact with the continuous conductor. The engine P traveling toward the Z end of the track, is

oppositely arranged. Its battery and hell I) have on the side next to the sectional con ductors a single brush in contact with the intermediate series, and on its opposite side a brush in contact with the continuous conductor,-and its battery and hell b have on one side two brushes which are in circuit with each other and in contact respectively with sections of the inner and outer series of conductors,and on the opposite side a brush in contact with the continuous conductor. By this arrangement, when the en.- gines P P are in the position represented in said Fig. 3, the striking bells b of both will have rung, the circuitin which both said hells exist extending, so far as the sectional eond uctors are concerned, through the section 0, cross wire 7L, and section M. Assuming for simplicity of explanation the engine P stat-ionary, when the engine P moves forward and places its forward right hand brush in contact with the section 0 said circuit will then extend through said section 0, cross wire 71., and section N In this arrangement, similarly to that of Fig. 1, the ringing of the hell I) always indicates an engine in front, and the ringing of the bell If indicates an engine in the rear.

In Fig. 4.- is shown a modified arrangement of sectional conductors in connection with which the system could be carried on. In this arrangement two series of sectional conductors are employed, and one continuous conduetor, being, as in the case of the other arran gement, either one of the rails of the track, or a special continuous conductor E. Thesections of the two series are of uniform length and are arranged so that their ends are even. The sections of the innerscries are designated S S S and the sect-ions of the outer series are designated T T T T. R R are two engines upon the track, the engine R traveling toward the Z end of the track, and the engine R toward the Y end of the track. The Z end of the section T is connected by a cross wire 72, with the Y end of the section S, the Z end of the section T with the Y end of the section and so on. The bells, batteries, and brushes,are arranged in the manner described with reference to Fig. 1. \Vhen the engines are in the position shown in Fig. 4- the bells b of each will be in circuit with each other through the brushes, the continuous conductor, the sectional conductors T and S and the cross wire h.

It will'ncw be understood that in my system, an engine upon a trackis guarded, both front and rearwardly,the side of the engine next to the series of sectional conductors is provided with a plurality of independent brushes, one of which is in one circuit and makes contact with the sections of one series of sectional conductors, and another of which brushes is in a separate circuit and makes contact with the sections of an independent series of sectional conductors. The first named series extends forward away from the engine, and sections in it are cross coupled to the sections of another and parallclseries, and a circuit set up in said sections thus cross coupled, 'in a bell and battery, and the brush thereto belonging, and in the continuous conductor,will be closed if another engine is upon the track in front of the engine referred to. The second named series extends rearwardly away from the engine, and its sections are cross coupled to the sections of another and parallel series, and a circuit set up in said sections so cross coupled, in a bell and battery, and the brush thereto belonging, and in the continuous conductor, will be closed by another engine upon the track to the rear of the engine under considoration.

If, instead of a plurality of series of sectional conductors, a single series of sectional conductors were employed, two engines approaching each other from opposite sides of one of the interspaces might come close to each other and collide at the point of such interspace without having signaled each others approach, but in my system, in which cross coupled sections lying in different aligned series, or connected groups lying in different aligned series and cross coupled, exist, such an overlapping of the sections is effected that when an engine has advanced so far that a brush is about to leave a section or the last member of a group of sections to pass onto a new section or new group of sections, the engine is not unprotected, for it is known before leaving the last section or the last group of sections that the track is clear for at least the distance ahead covered by the section or group of sections with which said passed group was cross coupled.

In the arrangement shown in Fig. '1 a connected group as I have termed it, of sections in one series, operates as one of the single sections, shown in Fig. 4, save that as the members of one group are interspersed so to speak with the members of othergroups, the ringing of the bells of engines in contact therewith is repeated so frequently, if they are single stroke bells, or interrupted so frequently,if they are continuously ringing bells, that the engineers are enabled to determine the rates of speeds of the engines. In said Fig. 1, the interrupting spaces in a group, are not non-conducting portions, but are as has been explained, members of another group, and an engine makes contact alternately with them, and if another engine be upon the track it will when within range of the signals, have its bell operated, when a given distance away, by the contact of the brush of the engine first named with the sections of a group which is connected with the sections of asecond group with which the brush of the second named engine is in contact.

Having thus described my invention, I claim:

1. In an electric railway signal system, a series of aligned conductor sections, electrically connected into groups, a second series of aligned conductor sections similarly connected into groups, the arrangement being such that each section exists between sections belonging to a group or groups other than its own, and groups in one series being connected with the respective groups of the other series, substantially as set forth.

2. In an electric railway signal system, a plurality of series of electric conductors each composed of a succession of conductor sections, non-adjacent members of one series of conductor sections being electrially connect ed to form a number of groups, the sections of each of such groups being interdisposed with the sections of other groups of the series, non-adjacent members of another series of conductor sections being similarly connected to form a number of groups, the sections of each of such groups being similarly interdisposed with the sections of other groups of the series, groups in different series being electrical] y cross coupled, substantially as set forth.

3. In an electric railway signal system, a plurality of electric conductors each composed of a succession of conductor sections, non-adjacent members of one succession or series being electrically connected to form a number of groups, the sections of the several distinct groups being interdisposed or alternated with each other,nonadjacent members of another succession or series being similarly connected to form a number of groups, the sections of the several distinct groups being similarly interdisposed or alternated with each other, groups in different series and abreast of different portions of the railroad track being electrically connected, substantially as set forth.

4. In an electric railway signal'system, a plurality of electric conductors which consist each of a series of sections, individual sections in different series. being electrically crosscoupled, a continuous conductor, a railway vehicle, brushes or contact devices carried by said railway vehicle each adapted to make contact with the sections of a selected conductor series, a battery and bell carried by said railway vehicle, i n circuit with each other, connected with one of said brushes, said battery having its positive pole in communication with said continuous conductor,-a second battery and bell also carried by said railway vehicle, in a separate circuit, also connected with one of said brushes and having its negative pole in com ll'llllllCtttlOllWltll said continuous conductor, substantially as set forth.

5. In an electric railway signal system, a plurality of conductors, one of which is continuous,and others of which each consist of a series of sections, individual sections in different series being electrically cross coupled, all being normallyout of circuit, a railway vehicle, a battery and bell mounted on said vehicle, in circuitwith each other, in circuit with the IIO continuous conductor and with one section of one series of sections,a second battery and be l mounted on said vehicle, in circuit with c.;' 11 other, in circuit with the continuous cont. :ctor, and with one section of a second series olsections, by which arrangement two circuits contemporaneously exist, one being the forward circuit existing in the continuous conductor, a sectional conductor abreast of the engine, and the first battery and bell and their connections,the second circuit, being the rear circuit, existing in the continuous conductor, a sectional conductor abreast of the engine, and the second battery and bell and their connections, substantially as set forth.

(3. In an electric railway signal system, a plurality of electrical conductors, a railway vehicle, brushes mounted free for lateral movement, upon opposite sides of said vehicle, yokes each uniting two brushes which respectively exist upon opposite sides of the vehicle, and -..:echanism connected with both yokes whereby their contemporaneous shifting respectively in opposite directions may be elfected to occasion the contact of the brushes with selected conductors, substantially as set forth.

7. In an electric railway signal system, a plurality of conductors, one of which is continuous, and others of which consist. each of a series of sections, individual sections in different series being eleetricallycross coupled, all said conductors being normally out of circuit, a railway track, a railway vehicle, a battery and bell in circuit with each other supported upon said vehicle, said battery being as to its positive pole in circuit with the continuous conductor, and as to its negative pole in circuit with a sectional conductor,a second battery and bell in circuit with each other and supported upon said vehicle, said battery being as to its negative pole in circuit with the continuous conductor, and as to its positive pole in circuit with another of the sectional conductors, the arrangement being such that the ringing of one bell indicates the presence of an engine in front and the ringing of the other bell indicates the presence of an engine in the rear, because of the presence in said engines in front or rear of circuit closing arrangements, substantially as described.

8. In an electric railway signal system, a plurality of conductors each composed of a series of conductor sections, non-adjacent members of one series of conductor sections being electrically connected to form a number of groups, the sections of each of such groups being interdisposed with the sections of other groups oranothergrou p of the series, non-adjacent members of another series of conductor sections being similarly connected to form a number of groups, the sections of each of such groups being similarly interdisposed with the sections of other groups or another group of the series, groups in differcut series being electrically cross coupled, a continuous conductor, a railway vehicle, a battery and bell supported upon said vehicle, electric connections by which one pole of the battery is placed in circuit with the continuous conductor, and the other pole of the battery is placed in circuit with a selected one of the series of conductor sections, substantially as set forth.

9. In an electric railway signal system, a plurality of conductors each composed of a successionofconductorsections,non-adjacent members of one series of sections being elec' trically connected to form a number ofgroups, the sections of each group being interdisposed or alternated with the sections of other groups,non-adjacent members of another series of conductor sections being similarly connected to form a number of groups, the sections of each group being similarly interdisposed or alternated with sections of other groups, groups in different series being crossconpled, a continuous conductor, a railway vehicle, brushes carried by said railway vehicle, respectively adapted to make contact with the sections of different conductor series, a battery and bell carried by said railway vehicle, in circuit with each other, connected with one of said brushes, said battery having its positive pole in communication with said continuous conductor,-a second battery and bell also carried by said vehicle, in a separate circuit from that first named, also connected with one of said brushes, said battery having its negative pole in communication with said continuous conductor, substantially as set forth.

10. In an electric railway signal system, a series of conductor sections, half of which are of one length and half of a different length, which sections are axially aligned and so arranged as to be of successively dissimilar lengths, said sections being by conducting connections formed into groups, the individnal sections composing a group being non-adjacent and existing each between sections belonging to a group or groups other than its own, substantially as set forth.

11. In an electric railway signal system, a railroad track, a railroad vehicle, a series of electrical conductors, brushes carried by said vehicle adapted to make contact with said conductors, two batteries carried by said vehicle, one of which batteries is in circuit with one half of the said brushes, and the otherof which batteries is in circuit with the other half of said brushes, said batteries having their poles arranged in opposite directions, substantially as set forth.

In testimony that I claim the foregoing as my invention, I hereunto sign my name this 26th day of October A. D. 1889.

STONIHVALL TOMPKINS.

In presence of WILBERT M. Yaonn, I'IENRY .T. DARNALL. 

